Hydropower projects may spell doom in case of earthquake, say geologists

Jotirmay Thapliyal

Tribune News Service

Dehradun, April 30

Geologists and environmentalists have said if a Nepal-like earthquake strikes Uttarakhand, there will be a large scale destruction and death owing to hydropower projects.

Dr SP Sati from the department of geology, HNB Garhwal University, Srinagar, said,” Barring Tehri Dam, which is rock and mud-filled structure, most of the hydropower dams in Uttarakhand are made up of reinforced concrete cement. The ability of these dams to withstand high-intensity tremors is highly questionable. They could collapse and lead to a large scale death and destruction downstream.”

“Uttarakhand falls in the central seismic gap region and is prone to earthquakes. The possibility of an earthquake of magnitude 8 cannot be ruled out in the state,” said Sati.

Referring to the occurrence of landslides as an immediate fallout of earthquakes, Sati said enormous landslides after an earthquake also affect the water containing capacity of dam reservoirs, which in long run also affect the life of dam.

Environmentalist Suresh Bhai, who has been opposing the construction of dams in Uttarakhand, said the Nepal earthquake was a wake up call for Uttarakhand, where dams were being built indiscriminately with a little concern for the environment and other norms. He said an earthquake could be detrimental to these dams and could wreak havoc in the region.

Dr Vineet Gahalaut, an expert in earthquake studies at National Geophysical Research Institute, said seismographic observations evidently revealed that with Indian plates constantly moving towards Eurasian plates resulting in collision, strain accumulation was certainly taking place in the Himalayan region, which could lead to an earthquake.

He said strong structures had the capacity to withstand tremors of high magnitude. Citing an example of the Fukushima power plant in Japan, Dr Gahalaut said that power plant withstood an earthquake of magnitude 9 in 2011 due to its seismological strong dam structure and it was only due to Tsunami later that power generation was somehow affected but the structure easily bore the brunt of tremors.

Gahalaut said similarly, a strong proper structure could easily bear an earthquake of high intensity. He, however, said norms for building these dams needed to be followed strictly. “Design parameters must be followed and a proper study be done before constructing any dam,” said Gahalaut.